The present invention concerns a multi-part header for attachment to a combine harvester, comprising a center part that is connectable by means of an attachment frame to the feed channel of a combine harvester and at least two side parts each to a corresponding lateral frame whose relative position to the center part is adjustable.
U.S. Pat. No. 4,956,966 discloses a header of the aforementioned kind that is connectable by means of an attachment frame to the feed channel of a combine harvester. The attachment frame is height-adjustably connected to the feed channel in order to be able to guide the header upon forward travel into a grain field at an appropriate spacing to the ground. The attachment frame is additionally pivotable about an axis that extends parallel to the forward travel direction of the combine harvester in order to be able to adjust, in transverse direction, the position of the header relative to the ground contour that is changing during forward travel of the combine harvester. The header comprises a central and two lateral belt conveyors which together are secured in a common frame. For greater working widths, such a header comprising only a single common frame is not adjustable precisely enough to a changing ground contour.
From EP 1 401 265 it is known to divide a header of the aforementioned kind across its working width into a central frame section and two wing frame sections laterally arranged thereto so that a header is provided with three frame sections distributed across its working width. The central frame section is connected by a fastening structure to the feed channel of the combine harvester. In this arrangement, the respective frame sections, upon forward travel of the combine harvester across a field to be harvested, can adjust with their respective partial working width to the respective changes in the ground contour of the field corresponding to the partial working width. This provides a better work result because the frame sections with their partial working width can react more precisely to differences in the ground contour across the working width of the header. The wing frame sections are connectable by means of the central frame section to the feed channel of a combine harvester. The wing frame sections are supported by the central frame section.
Due to the combine harvesters becoming more and more powerful and the working widths of the headers therefore increasing more and more, the weight of the headers has increased more and more. The fastening structure with which the header is to be connected to the feed channel of the combine harvester must transmit increasingly greater forces and therefore must be designed in turn to be increasingly heavier. Also, the main frame that extends across the working width of the header becomes increasingly heavier. Due to the increasing weights, it is becoming more and more difficult to adjust a multi-part header with a sufficiently fast response time to changing ground contours upon forward travel of the combine harvester.
It is the object of the present invention to improve the connection of the header to the feed channel of a combine harvester in order to still enable, even for great working widths of a header, a ground adaptation with a fast response time.